"bers roulants" meaning in Français

{
  "anagrams": [
    {
      "word": "balustrerons"
    }
  ],
  "categories": [
    {
      "kind": "other",
      "name": "Formes de locutions nominales en français",
      "parents": [],
      "source": "w"
    },
    {
      "kind": "other",
      "name": "Français",
      "orig": "français",
      "parents": [],
      "source": "w"
    }
  ],
  "forms": [
    {
      "form": "ber roulant",
      "tags": [
        "singular"
      ]
    }
  ],
  "lang": "Français",
  "lang_code": "fr",
  "pos": "noun",
  "pos_title": "Forme de locution nominale",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "Exemples en français",
          "parents": [],
          "source": "w"
        }
      ],
      "examples": [
        {
          "bold_text_offsets": [
            [
              20,
              33
            ]
          ],
          "ref": "Félix Laroche, Ports maritimes, tome second, Baudry et Cⁱᵉ, Paris, 1893, page 183",
          "text": "Cependant, avec les bers roulants, par suite de leur faible pente, l’effort total de traction n’est, en général, que de 40 à 60 % de celui qu’exigent les bers glissants."
        }
      ],
      "form_of": [
        {
          "word": "ber roulant"
        }
      ],
      "glosses": [
        "Pluriel de ber roulant."
      ],
      "id": "fr-bers_roulants-fr-noun-Q5Nx~Rve"
    }
  ],
  "sounds": [
    {
      "ipa": "\\bɛʁ ʁu.lɑ̃\\"
    }
  ],
  "tags": [
    "form-of",
    "masculine"
  ],
  "word": "bers roulants"
}

{
  "anagrams": [
    {
      "word": "balustrerons"
    }
  ],
  "categories": [
    "Formes de locutions nominales en français",
    "français"
  ],
  "forms": [
    {
      "form": "ber roulant",
      "tags": [
        "singular"
      ]
    }
  ],
  "lang": "Français",
  "lang_code": "fr",
  "pos": "noun",
  "pos_title": "Forme de locution nominale",
  "senses": [
    {
      "categories": [
        "Exemples en français"
      ],
      "examples": [
        {
          "bold_text_offsets": [
            [
              20,
              33
            ]
          ],
          "ref": "Félix Laroche, Ports maritimes, tome second, Baudry et Cⁱᵉ, Paris, 1893, page 183",
          "text": "Cependant, avec les bers roulants, par suite de leur faible pente, l’effort total de traction n’est, en général, que de 40 à 60 % de celui qu’exigent les bers glissants."
        }
      ],
      "form_of": [
        {
          "word": "ber roulant"
        }
      ],
      "glosses": [
        "Pluriel de ber roulant."
      ]
    }
  ],
  "sounds": [
    {
      "ipa": "\\bɛʁ ʁu.lɑ̃\\"
    }
  ],
  "tags": [
    "form-of",
    "masculine"
  ],
  "word": "bers roulants"
}